1. Field of the Invention
The invention relates generally to a stereomicroscopy system for viewing an object or an intermediate image produced of an object. This intermediate image may be a vertically and horizontally inverted image of an object, and the microscopy system may be utilized in microsurgery, in particular, for carrying out eye surgeries.
2. Background Art
Stereomicroscopes are known in the art. FIG. 11 schematically depicts a beam path of a conventional stereomicroscope. In the conventional stereomicroscope, the viewer looks with his two eyes 901 and 902 into a left ocular 903 and a right ocular 904, respectively, and views, for example, an object positioned in an object plane 905 of the microscope. The oculars 903 and 904 together with image inverting prisms 915 and tube lenses 913 form the tube which functions as a binocular Keplerian telescope. The object is perceived by the viewer with a stereoscopic spatial impression, because a beam bundle 907 issuing from the object and extending on the left, in respect of a central plane 906 of the microscope, to a collective lens 909 of the microscope enters the collective lens 909 on the left and is imaged into the left ocular 903, whereas a beam bundle 908 issuing from the object on the right, in respect of the central plane 906, also enters the collective lens 909 on the right and is imaged into the right ocular 904. The objective system furthermore comprises an a focal zoom system 911 for changing the magnification. The oculars 903, 904 each comprise a tube lens 913 and a Schmidt-Pechan prism 915. The Schmidt-Pechan prisms are required to provide a vertically and horizontally rectified image of the object, the orientation of which has been inverted by the objective.
The conventional stereomicroscope may also be used in eye surgery to view an eye fundus 916 of an eye 917 of a patient. For this purpose, an ophthalmoscopic lens 919 is positioned in front of the patient""s eye and produces an intermediate image of the eye fundus 916 in the object plane 905 of the microscope. The intermediate image of the eye fundus is then viewed by the surgeon through the stereomicroscope.
In the configuration of the stereomicroscope and the ophthalmoscopic lens shown in FIG. 11, due to the change in the image orientation and the stereoscopic sightline through the ophthalmoscopic lens, the eye fundus is perceived by the surgeon vertically and horizontally inverted and, in addition, pseudo-stereoscopic, i.e., as far as the depth perception is concerned, front and back appear inverted to the surgeon. In order to remove this problem, the correct image orientation must be re-established, on the one hand, and, on the other hand, the two stereo channels of the microscope must be interchanged, i.e., the beam bundle 907 issuing from the object plane 905 on the left must be supplied to the right eye 902 of the surgeon, and the beam bundle 908 issuing on the right must be supplied to the left eye 901 of the surgeon.
A stereomicroscopy system is disclosed for viewing an object and/or an intermediate image produced of an object, in microsurgery. The stereomicroscopy system includes an objective system with an object plane for positioning the object and/or the intermediate image to be viewed. The stereomicroscopy system also includes a beam interchanging and image inverting system. The beam interchanging and image inverting system supplies a first beam bundle directed to the left from the object plane in the direction of the objective system to the right of the objective system. The beam interchanging and image inverting system also supplies a second beam bundle directed to the right from the object plane in the direction of the objective system to the left of the objective system. The beam interchanging and image inverting system also inverts image orientations of the two beam bundles. The beam interchanging and image inverting system includes at least one Porro prism of the second kind.
Other aspects and advantages of the invention will be apparent from the following description and the appended claims.